The present invention relates to a hydraulic braking force multiplying device for use in an automobile.
A hydraulic braking force multiplying device is, in general, connected to a master cylinder for actuating the master cylinder. Devices of this type can be classified into two groups depending on the movement of the brake pedal: one of which is called as "stroke type," in which stroke of an input shaft of the braking force multiplying device corresponds to an amount which is required to advance a piston in the master cylinder; and the other which is referred to as the so-called non-stroke type, in which the necessary stroke of the input shaft is only a small amount required to actuate a valve mechanism incorporated in the device. The former type is attended with the drawbacks that a driver suffers from fatigue, and that the construction becomes a large-sized and complicated one, while the latter type involves the shortcomings that failure in the power source results in failure of the entire system.